How do I alter a to behave like b, while keeping my %c?
That is how to make the final line print ab while using the construct $c{a} = 'a' somehow in a. 
sub a {
  my $ref = shift;
  my %c = %$ref;
  $c{a} = 'a';
}

sub b {
  my $c = shift;
  $$c{b} = 'b';
}

my %c;
&a(\%c);
&b(\%c);
print foreach (keys %c);

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In reply to References by Cine

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